Joakim Riikonen
University of Eastern Finland
ChemistryPorous siliconDrug deliverySiliconMesoporous material
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Publications 59
#1Anna LähdeH-Index: 10
Last. Vesa-Pekka LehtoH-Index: 35
view all 9 authors...
#1Rinez Thapa (University of Eastern Finland)H-Index: 1
#2Tuomo Nissinen (University of Eastern Finland)H-Index: 8
Last. Joakim Riikonen (University of Eastern Finland)H-Index: 19
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Abstract Scandium has several applications in advanced technology, but its wider utilization is restricted by the limited supply. Scandium exists in low concentration in ores and therefore the conventional extraction methods are difficult, uneconomical, and often hazardous to the environment. Adsorption technology is more sustainable method to extract scandium, because of low energy consumption and scalability. However, selectivity and stability of adsorbents are often inadequate. The present pa...
1 CitationsSource
#1Joakim Riikonen (UDS: University of Strasbourg)H-Index: 19
#1Joakim Riikonen (UDS: University of Strasbourg)H-Index: 1
Last. Vesa-Pekka Lehto (University of Eastern Finland)H-Index: 35
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Mesoporous silicon (PSi) is an emerging nanomaterial studied in e.g. biomedical, sensor and energy applications. In many applications, a major obstacle in its commercial use is the instability of its surfaces, especially when functionalized with organic molecules. In the present work, we introduce a surface functionalization method for PSi, in which carbonized surface of silicon is functionalized with terminal alkenes. A good surface coverage of 0.3 molecules per nm2 was achieved and the materia...
1 CitationsSource
Abstract Silicon is a promising alternative anode material for LIBs because it has ten times higher capacity than the currently used graphite giving the possibility to even double to capacity of the total battery cell. The high specific capacity is essential in the electric vehicles and portable electronic devices. However, silicon anodes are unstable during the charge/discharge cycles due to the large volume change of silicon leading to cracking of the silicon particles, which results in poor c...
#1Konstantin Tamarov (University of Eastern Finland)H-Index: 1
#2Joseph Swanson (WCUPA: West Chester University of Pennsylvania)
Last. Joakim Riikonen (University of Eastern Finland)H-Index: 19
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Metal-assisted catalytic etching (MACE) involving Ag deposited on Si particles has been reported as a facile method for the production of Si nanowires (Si NWs). We show that the structure of Si particles subjected to MACE changes dramatically in response to changing the loading of the Ag catalyst. The use of acetic acid as a surfactant and controlled injection of AgNO3(aq) enhanced Ag deposition. The use of acetic acid and controlled injection of H2O2 not only facilitated optimization of the etc...
#1Remi Kamakura (OUH: Oulu University Hospital)H-Index: 1
#2Miia Kovalainen (OUH: Oulu University Hospital)H-Index: 1
Last. Karl-Heinz Herzig (Poznan University of Medical Sciences)H-Index: 48
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Abstract Novel treatment methods for obesity are urgently needed due to the increasing global severity of the problem. Gastrointestinal hormones, such as GLP-1 and PYY, are secreted by the enteroendocrine cells, playing a critical role in regulating food intake. Digested nutrients trigger the secretion of these hormones, which have a very short half-life. α-Linolenic acid (αLA) has been shown to stimulate GLP-1 secretion, however, chemical instability and fast uptake in the small intestine hinde...
2 CitationsSource
#1Jimi Rantanen (University of Eastern Finland)H-Index: 3
#2Dorota Majda (Jagiellonian University)H-Index: 14
Last. Vesa-Pekka Lehto (University of Eastern Finland)H-Index: 35
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Abstract The atomic-scale structure of amorphous SBA-15 materials with different pore sizes (6.7–12.7 nm) was investigated using pair distribution functions calculated from the X-ray total scattering data. The data was collected with a laboratory X-ray powder diffraction instrument instead of a synchrotron often considered necessary for pair distribution function analysis. A 3D model of the atomic structure within the pore walls was determined based on the pair distribution function analysis, an...
#1Miia Kovalainen (University of Oulu)H-Index: 12
#2Remi Kamakura (University of Oulu)H-Index: 3
Last. Vesa-Pekka Lehto (University of Eastern Finland)H-Index: 35
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Abstract Despite extensive efforts to develop delivery systems for oral administration, subcutaneous (s.c.) injection remains the most common way to administer peptide drugs. To limit the number of frequent injections, sustained release systems that are easy to produce, suitable for various drugs, safe and biodegradable are urgently needed. Porous silicon (PSi) has been recognized to be one of the most promising materials for s.c. peptide delivery, but its biodegradation in s.c. tissue has not b...
3 CitationsSource
#1Joakim Riikonen (University of Eastern Finland)H-Index: 19
#2Wujun Xu (University of Eastern Finland)H-Index: 14
Last. Vesa-Pekka Lehto (University of Eastern Finland)H-Index: 35
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Abstract When poor aqueous solubility of active pharmaceutical ingredients is encountered during a drug formulation process, the toolbox typically utilized contains pharmaceutical salts, co-crystals, solid dispersions, cyclodextrins, lipids, liposomes and nanocrystals etc. Especially in the pharmaceutical industry, the option which confers the greatest benefit with the lowest risk is usually chosen. Several factors affect the final decision, but new technologies should also be considered especia...
11 CitationsSource